1. Field of the Invention
The present invention mainly relates to an apparatus for winding a curtain such as a motor-driven roll blind to be mounted on a rear windshield of a car.
2. Description of the Related Art
FIG. 4 is a perspective view showing the whole construction of a prior art a curtain winding apparatus; and FIG. 5 is a front view showing the left half of the prior art curtain winding apparatus. In FIGS. 4 and 5, reference numeral 1 indicates a long-size box shaped base; 2 and 3 indicate holders fitted at both the longitudinal end portions of the base 1 so as to be laterally symmetric to each other; 4 is a blind as the curtain; 5 is a winding mechanism disposed in the base 1 for holding the base end portion of the blind 4 and winding the blind 4; 6 is a drawing pipe mounted on the upper end portion (leading end) of the blind 4; 7 is a roller having an elastic body such as an O-ring around the outer periphery thereof; 8 is a roller holder for rotatably mounting the roller 7 at the end portion of the drawing pipe 6; and 10, 10 are drawing mechanisms disposed to be laterally symmetric to each other for holding the drawing pipe 6 and drawing the blind 4.
Each drawing mechanism 10 includes two arms 10a, 10b connected to each other by means of a pin 11 as an articulated joint; and an arm holder 12 for fixing the arm 10b on the base end side to the holder 2 or 3. The arms 10a, 10b of the right and left drawing mechanisms 10 are provided to be respectively flexible within the same plane containing the base 1, and are usually energized in the direction of stretching the articulated joints by springs or the like (not shown) contained therein. As shown in FIG. 5, the end portion of the arm 10b on the base end side is connected to the arm holder 12 by means of a pin 13 in such a manner as to be rotabaly supported around the pin 13 within the flexible plane of the arms 10a, 10b. The leading end of the arm 10a on the leading end side is pin-connected to the end portion of the drawing pipe 6 by means of a screw 9. Accordingly, when the articulated joint (pin 11) of the arms 10a and 10b of each of the right and left drawing mechanisms 10 is expanded/contracted (flexibly operated) as shown in FIG. 5, the base end of the arm 10b is turned around the pin 13, so that the arms 10a, 10b connected to the drawing pipe 6 equivalent to a link are expanded/contracted within the plane containing the base 1 as a whole.
The arm holder 12 is fixed on the holder 2 or 3 by means of a bolt 15 and a nut 16 through a toothed washer 14. In this case, the arm holder 12 can be turned around the bolt 15 by loosening the bolt 15, and accordingly, the mounting angle of the drawing mechanism 10 (mounting angle within a plane perpendicular to the longitudinal direction of the base 1) can be adjusted in accordance with the type of car.
FIG. 6 is a construction view showing essential portions of the winding mechanism 5. The winding mechanism 5 has a winding pipe 17 provided with a slit 17a. By insertion of a slip-off preventive portion 4a provided at the base end portion of the blind 4 into the slit 17a, the base end portion of the blind 4 is engaged with the winding pipe 17.
FIG. 7 is a construction view showing the internal structure of the winding mechanism 5. The winding mechanism 5 has a drive portion case 18, a drive motor 19 provided in the case 18, and a joint 20 fitted to an output shaft 19a of the drive motor 19, in addition to the above-described winding pipe 17. The joint 20 is connected to the winding pipe 17 by means of a tapping screw 21. Reference numeral 22 indicates an angular pin fixed at the center of the leading end of the drive portion case 18. The drive portion case 18 is fixed at a boss portion 2a of the holder 2 by means of the angular pin 22. Reference numeral 23 indicates an end surface plate fixed at the end portion of the winding pipe 17. By insertion of a round pin 24 fixed at the center of the end surface plate 23 into the boss portion 3a of the holder 3, the winding pipe 17 is rotatably supported on the holder 3. A limit switch (not shown) for restricting the rotational angle of the drive motor 19 is contained in the drive portion case 18. By the use of the limit switch, the drawing length of the blind 4 can be adjusted in accordance with the type of car.
FIG. 8 is a view showing the mounting mode of the curtain winding apparatus. In the figure, reference numeral 25 indicates a mounting leg slidable in the longitudinal direction within an L-shaped hook 1a of the base 1. By hooking of the mounting leg 25 to a bracket 28 fixed on a rear shelf 27 on the rear side of the rear seat of a car by means of a bolt 26, the base 1 as the main portion of the curtain winding apparatus is mounted on the car. An operational switch (not shown) is mounted on a portion near a driver's seat.
Next, the operation of the winding apparatus of the present invention will be described. Upon the mounting of the curtain winding apparatus, since the inclination of a rear windshield 30 as shown in FIG. 8 is different in accordance with the type of car, the mounting angles of the arm holders 12 of the right and left drawing mechanisms 10 are adjusted in accordance with the inclination of the rear windshield 30 by loosening the bolts 15 shown in FIG. 5, so that the angles of the right and left drawing mechanisms 10 are made to correspond to each other. At this time, when the blind 4 is drawn, the mounting angles of the arm holders 12 are adjusted such that the portions where the rollers 7 are contacted with the rear windshield 30 of the car are lower than the upper ends of the rear windshield 30 by about 5 cm. In such a mounting state, the drive motor 19 of the winding mechanism 5 is normally or reversely rotated by turning on the operational switch (not shown), and the rotation is transmitted to the winding pipe 17 through the joint 20. The winding pipe 17 is thus rotated as shown by the arrow in FIG. 8 around the round pin 24. Since the blind 4 is usually applied with a tensile strength by the drawing mechanisms 10, it is wound or drawn in the stretched state in accordance with the rotation of the winding mechanism 5. At this time, the arms 10a, 10b are bent in the direction shown by the arrow in FIG. 5, and are expanded/contracted as a whole. The drive motor 19 is automatically stopped at the drawing upper end or the winding lower end by the limit switch (not shown) contained in the drive portion case 18 shown in FIG. 7, thus stopping the winding or drawing operation. When the blind 4 is drawn as shown in FIG. 8, the mounting angles of the arm holders 12 are adjusted such that the portions where the rollers 7 are contacted with the rear windshield 30 of the car are lower than the upper ends of the rear windshield 30 by about 5 cm, and accordingly the rollers 7 are rolled from the positions where the rollers 7 are contacted with the windshield 30 to the upper ends of the rear windshield 30, and thereby at the upper ends of the rear windshield 30, the rollers 7 are pressed on the rear windshield 30 by the deflected amounts of the drawing mechanisms 10, thus preventing the rattling of the blind 4 during running of the car.
In addition, since the mounting leg 25 is slidable in the longitudinal direction of the L-shaped hook 1a of the base 1 as shown in FIG. 8, it can be provided on an empty position without any obstacle (for example, speaker, air cleaner, stop lamp or the like) on the rear shelf 27, thus making it possible to enhance the mounting versatility to various types of cars.
The prior art curtain winding apparatus having the above-described construction, however, has the following disadvantages: namely, the positions where the rollers 7 are contacted with the rear windshield 30 must be adjusted while the mounting angles of the right and left independent drawing mechanism 10 are made to correspond to each other, thus taking a lot of labor and time; and further, the slit 17a is provided in the winding pipe 17 constituting the winding mechanism 5 and the base end portion of the blind 4 is fixedly inserted in the slit 17a, and consequently operational noise of the drive motor 19 is exteriorly leaked from the slit 17a to the extent being offensive to the ear.